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. 2021 May;32(9):955-970.
doi: 10.1177/1045389X21991237. Epub 2021 Feb 11.

Experimental assessment of a linear actuator driven by magnetorheological clutches for automotive active suspensions

William East  1 , Jérôme Turcotte  1 , Jean-Sébastien Plante  1 , Guifré Julio  1
Affiliations

Experimental assessment of a linear actuator driven by magnetorheological clutches for automotive active suspensions

William East et al. J Intell Mater Syst Struct. 2021 May.

Abstract

The main functions of automotive suspensions are to improve passenger comfort as well as vehicle dynamic performance. Simultaneously satisfying these functions is not possible because they require opposing suspension adjustments. This fundamental design trade-off can be solved with an active suspension system providing real-time modifications of the suspension behavior and vehicle attitude corrections. However, current active suspension actuator technologies have yet to reach a wide-spread commercial adoption due to excessive costs and performance limitations. This paper presents a design study assessing the potential of magnetorheological clutch actuators for automotive active suspension applications. An experimentally validated dynamic model is used to derive meaningful design requirements. An actuator design is proposed and built using a motor to feed counter-rotating MR clutches to provide upward and downward forces. Experimental characterization shows that all intended design requirements are met, and that the actuator can output a peak force of ±5300 N, a peak linear speed of ±1.9 m/s and a blocked-output force bandwidth of 92 Hz. When compared to other relevant technologies, the MR approach simultaneously shows both better force density and speeds (bandwidth) while adding minimal costs and weight. Results from this experimental assessment suggest that MR slippage actuation is promising for automotive active suspensions.

Keywords: Automotive; active suspension; and pinion mechanism; controlled slippage actuator; magnetorheological clutches; rack.

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Conflict of interest statement

Declaration of conflicting interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Figures

Figure 1.
Figure 1.
Hydraulic active suspension system of Williams’s F1 (Howard, 2001).
Figure 2.
Figure 2.
Direct-drive electromagnetic active suspension system of BOSE (Suspension Spot, 2018).
Figure 3.
Figure 3.
Electromagnetic hydrostatic active suspension system of ClearMotion (Citroën Vie, 2018).
Figure 4.
Figure 4.
Geared electric motor active suspension system of Audi (2017).
Figure 5.
Figure 5.
Reflected mass of an electromagnetic geared motor compared to a MR clutch driven system.
Figure 6.
Figure 6.
Cut view of Exonetik’s 37 N·m MR clutch.
Figure 7.
Figure 7.
MR actuator CAD in the test vehicle (BMW 330ci).
Figure 8.
Figure 8.
Sprung mass vertical acceleration PSD w/o active suspension (wheel reference frame).
Figure 9.
Figure 9.
Ideal actuator speed-force diagram (wheel reference frame).
Figure 10.
Figure 10.
Working principle diagram of the MR actuator.
Figure 11.
Figure 11.
Cut view of the actuator in fully compressed and fully out position (spring removed).
Figure 12.
Figure 12.
(a) Inside view of the transfer case and gearing and (b) exploded view of the main sub-assemblies of the actuator.
Figure 13.
Figure 13.
MR actuator assembled prototype.
Figure 14.
Figure 14.
Standard upright versus inverted configuration of a Macpherson strut.
Figure 15.
Figure 15.
Test bench for MR clutch and motor characterization.
Figure 16.
Figure 16.
Exonetik 37 N·m MR clutch characterization results.
Figure 17.
Figure 17.
KDE700XF-295-G3 electric motor power and torque curve.
Figure 18.
Figure 18.
MR actuator on MTS 322-31 test rig.
Figure 19.
Figure 19.
MR actuator force to current relationship (1 Hz) (actuator reference frame).
Figure 20.
Figure 20.
MR actuator force hysteresis (0.5 Hz) (actuator reference frame).
Figure 21.
Figure 21.
MR actuator parasitic force (actuator reference frame).
Figure 22.
Figure 22.
MR actuator peak linear speed test setup.
Figure 23.
Figure 23.
MR actuator linear speed (actuator reference frame).
Figure 24.
Figure 24.
Model-referenced feedforward controller.
Figure 25.
Figure 25.
MR actuator blocked output force bandwidth (actuator reference frame).
Figure 26.
Figure 26.
Detailed mass comparison of stock suspension versus MR actuator suspension.
See this image and copyright information in PMC

References

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